Have you gone into system set up yet? have you ever FTP'ed into your Xbox?

You need to set the IP address as static in the system set up. then when you done that scroll down the bottom of the set-up screen and make sure that you save the settings. then turn you box off. Check that whole cable thing is cool. I use a cross-over. I got rid of my hand made one and the trnsfer speed went from 300Kbps to 8,000Kbps.

There are heaps of little tricks and tips i learned when i set mine up. ask if more help is needed